Kurt Jung - Beginning Lua programming

Beginning
Lua Programming

Beginning
Lua Programming

Kurt Jung and Aaron Brown

Wiley Publishing, Inc.

Beginning Lua Programming

Published by

Wiley Publishing, Inc.

10475 Crosspoint Boulevard Indianapolis, IN 46256

www.wiley.com

Copyright 2007 by Wiley Publishing, Inc., Indianapolis, Indiana

Published simultaneously in Canada

ISBN: 978-0-470-06917-2

10 9 8 7 6 5 4 3 2

1MA/SS/QR/QX/IN

Library of Congress Cataloging-in-Publication Data

Jung, Kurt, 1956

Beginning Lua programming / Kurt Jung and Aaron Brown.

p. cm.

ISBN-13: 978-0-470-06917-2 (pbk.)

1. Lua (Computer program language) I. Brown, Aaron, 1973- II. Title.

QA76.73.L82J96 2007

005.13'3--dc22

2006036460

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Lua 5.0 Copyright 1994-2006, Lua.org, PUC-Rio

Lua 5.1 Copyright 2006, Lua.org

The Lua logo was designed by Alexandre Nakonechnyj.

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About the Autuors

Between his first programs submitted to a Burroughs 5500 on Hollerith punch cards and his latest programs tapped into a Palm Pilot, Kurt Jung has been the principal programmer on various projects ranging from airline yield management to state machine-driven workflow.

Aaron Brown began programming in elementary school on a Commodore 64. He plays various musical instruments and speaks Esperanto.

Credits

Acquisitions Editor

Kit Kemper

Development Editor

Maryann Steinhart

Technical Editor

Adam Dumas

Production Editor

Rachel Meyers

Copy Editor

Kathryn Duggan

Editorial Manager

Mary Beth Wakefield

Production Manager

Tim Tate

Vice President and Executive Group

Richard Swadley

Vice President and Executive Publisher

Joseph B. Wikert

Graphics and Production Specialists

Denny Hager

Shane Johnson

Barry Offringa

Heather Ryan

Quality Control Technician

John Greenough

Jessica Kramer

Project Coordinator

Erin Smith

Proofreading and Indexing

Techbooks

Anniversary Logo Design

Richard Pacifico

Acknowledgments

This project has had strong and capable guidance from Kit Kemper and Maryann Steinhart at Wiley Publishing. Maryann was remarkably responsive in making sure our questions were answered promptly. May Kit and Maryann land leading roles when Hollywood makes Beginning Lua Programming into a major motion picture.

Laurels and commendations go to Adam Dumas, the best technical editor a book could possibly have. Adam's thoroughness and attention to detail uncovered a humbling number of issues with the manuscript, all of which were brought to our attention in the most courteous and constructive way and often with insightful corrections.

The Lua community provided much help and many answers. Thanks go to Roberto Ierusalimschy, Waldemar Celes, and Luiz Henrique de Figueiredo for creating a remarkable language about which it is easy to remain enthusiastic. Roberto and Luiz Henrique also answered some specific questions related to this book. The following people were very helpful in answering questions about their respective projects: Andre Carregal (LuaForge and the Kepler Project), Mark Hamburg (Adobe Lightroom), Asko Kauppi (LuaSDL and LuaX), and Kein-Hong Man (ChunkSpy and the No-Frills Introduction to Lua 5.1 VM Instructions).

From Kurt Jung: Collaborating with an individual as gifted and inventive as Aaron has been an entirely rewarding experience. It's with great pleasure that I look forward to future projects together. Multajn dankojn, mia bonamiko.

The encouragement of my mother and other family members has been greatly appreciated. Although writing this book may have given me a great excuse to delay various chores (most notably the one involving a lawn mower) and household repairs, it never interfered with the frequent, pleasurable, and bonding walks I take with my wife Maura, daughter Laura, and our bundle of canine energy, Brilla. I owe the greatest thanks to Maura for her support during this endeavor.

From Aaron Brown: Apart from being my programming mentor, inviting me to collaborate on this book with him, and being an all-around nice guy, Kurt Jung is one of the few true kindred spirits I have encountered. Mia teraplano estas plena je angiloj!

Cathy Lewis gave advice on the writing process at a pivotal moment. She (in her capacity as my girlfriend), my bandmates, and family also deserve thanks for their understanding of my reduced availability while slaving in the book mines.

Special thanks to Mom (a.k.a. Marty Brown), who bought me that first computer so long ago.

Introduction

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